On Saturdays, Leslie earns $14 per hour for yard work and an extra amount for dog walking

Solve this system of equations

olga_2 [115]

Answer:

D) x = 4, y = -2, z = 3

Step-by-step explanation:

x = 3z − 5

2x + 2z = y + 16

2(3z - 5) + 2z = y + 16

6z - 10 + 2z = y + 16

8z = y + 26 ---> (A)

7x − 5z = 3y + 19

7(3z - 5) - 5z = 3y + 19

21z - 35 - 5z = 3y + 19

16z = 3y + 54 ---> (B)

8z = y + 26

16z = 3y + 54

2(y + 26) = 3y + 54

2y + 52 = 3y + 54

y = -2

8z = -2 + 26

8z = 24

z = 3

x = 3(3) - 5

x = 4

8 0

3 years ago

HELP ASAP!!!! SO STUCK ON THIS! Will give brainliest IF CORRECT! :) please help! Be sure please!

vlada-n [284]

If I can read the #'s correctly:
add the yes answers together 23+147 = 170
add the no answers together 112+48= 160

so your ratio of haves to have nots is 170 to 160

but both sides can be divided by 10, so it can be simplified to 17 to 16.

Good Luck!

4 0

3 years ago

Read 2 more answers

Need an explanation on number 44 to why E is correct

aliina [53]

Before we can make sure that E is correct, we need to make the denominator is equal with questions and the choices or convert into decimal.

2/3 = 0.66

1/3=0.33

1/5=0.2

2/6=1/3 = 0.33

1/2 = 0.5

7/10 = 0.7

7/9 = 0.77

The question is :

2/3 < x < 7/9

0.66 < x < 0.77

We need to divide into 2 parts :

0.66 < x

x < 0.77

So we need to find the answer that x is greater that 0.66 and we got 7/10. And 7/10 is less than 7/9.

Hope this helps. Please ask if you don't understand.

6 0

3 years ago

PLEASE HELP I NEED THIS

Elis [28]

Answer:

B

Step-by-step explanation:

3 0

3 years ago

In the book Essentials of Marketing Research, William R. Dillon, Thomas J. Madden, and Neil H. Firtle discuss a research proposa

MakcuM [25]

Answer:

Null hypothesis: $p_{1} = p_{2}$

Alternative hypothesis: $p_{1} \neq p_{2}$

$z=\frac{0.179-0.15}{\sqrt{0.17(1-0.17)(\frac{1}{140}+\frac{1}{60})}}=0.500$

$p_v =2*P(Z>0.500)=0.617$

So the p value is a very low value and using any significance level for example $\alpha=0.05, 0,1,0.15$ always $p_v>\alpha$ so we can conclude that we have enough evidence to FAIL to reject the null hypothesis, and we can say the two proportions NOT differs significantly.

Step-by-step explanation:

Data given and notation

$X_{1}=25$ represent the number of homeowners who would buy the security system

$X_{2}=9$ represent the number of renters who would buy the security system

$n_{1}=140$ sample 1

$n_{2}=60$ sample 2

$p_{1}=\frac{25}{140}=0.179$ represent the proportion of homeowners who would buy the security system

$p_{2}=\frac{9}{60}= 0.15$ represent the proportion of renters who would buy the security system

z would represent the statistic (variable of interest)

$p_v$ represent the value for the test (variable of interest)

Concepts and formulas to use

We need to conduct a hypothesis in order to check if the two proportions differs , the system of hypothesis would be:

Null hypothesis: $p_{1} = p_{2}$

Alternative hypothesis: $p_{1} \neq p_{2}$

We need to apply a z test to compare proportions, and the statistic is given by:

$z=\frac{p_{1}-p_{2}}{\sqrt{\hat p (1-\hat p)(\frac{1}{n_{1}}+\frac{1}{n_{2}})}}$ (1)

Where $\hat p=\frac{X_{1}+X_{2}}{n_{1}+n_{2}}=\frac{25+9}{140+60}=0.17$

Calculate the statistic

Replacing in formula (1) the values obtained we got this:

$z=\frac{0.179-0.15}{\sqrt{0.17(1-0.17)(\frac{1}{140}+\frac{1}{60})}}=0.500$

Statistical decision

For this case we don't have a significance level provided $\alpha$ , but we can calculate the p value for this test.

Since is a two sided test the p value would be:

$p_v =2*P(Z>0.500)=0.617$

So the p value is a very low value and using any significance level for example $\alpha=0.05, 0,1,0.15$ always $p_v>\alpha$ so we can conclude that we have enough evidence to FAIL to reject the null hypothesis, and we can say the two proportions NOT differs significantly.

6 0

3 years ago